Carbohydrate utilization and short chain fatty acid production in Bifidobacteria

In the first stage of life infants go through rapid growth and development and have high nutritional needs. During this first 6 months of life breast milk is considered to provide a complete postnatal nutrition. Positive benefits of breastmilk have been extensively documented and it is a known fact that breastfed infants show a domination of Bifidobacterial species in the gut. The colonization pattern has been revealed to be majorly affected by human milk oligosaccharides (HMOs) found in breast milk. HMOs are not digested by the infant and will as a result reach the colon where different strains of Bifidobacteria metabolise them and produce metabolites, mainly in the form of short chain fatty acids (SCFA) where some might be beneficial to the host. The study included seven different Bifidobacteria strains that were test grown in five different mediums with different carbon sources with a total of 42 samples repeated in three parallels. DNA quantification was performed with the use of qPCR and short chain fatty acid profiles were measured with the use of high-performance liquid chromatography. In conclusion the results demonstrated differences in HMO utilization and SCFA production among the different strains. It was clearly demonstrated that Bifidobacterium longum subsp. Infantis has the best utilization and growth abilities on HMOs which may reflect their abundance in the infant gut. The main metabolite of carbohydrate fermentation performed by Bifidobacteria strain was acetic acid and the results also confirmed that the most common infant type Bifidobacteria strains are the main producers of lactic acid